Lugo is a city in northwestern Spain in the autonomous community of Galicia. It is the capital of the province of Lugo. The municipality had a population of 99,241 in 2013, which makes it the fourth most populated city in Galicia.Lugo is the only city in the world to be surrounded by completely intact Roman walls, which reach a height of 10 to 15 metres along a 2,117-metre circuit ringed with 71 towers. The walk along the top is continuous round the circuit, and features ten gates. These 3rd century walls are protected by UNESCO as a World Heritage Site. The bridge over the Minho is essentially of Roman date, though many repairs over the centuries have effaced its Roman character.